File Coverage

blib/lib/Algorithm/Prefixspan.pm

Criterion	Covered	Total	%
statement	13	15	86.6
branch			n/a
condition			n/a
subroutine	5	5	100.0
pod			n/a
total	18	20	90.0

package Algorithm::Prefixspan;
use 5.008001;
use strict;
use warnings;

use Moo;
use MooX::Types::MooseLike::Base qw( ArrayRef HashRef Num Int Str );
use namespace::clean;
use Carp;

our $VERSION = "0.02";

has data => (
    is       => 'rw',
    isa      => ArrayRef,
    required => 1,
);

has out => (
    is       => 'rw',
    isa      => HashRef,
);

has minsup => (
    is      => 'rw',
    isa     => Int,
    default => sub { 2 },
);

has len => (
    is      => 'rw',
    isa     => Int,
    default => sub { 1 },
);

sub run {
  my $self = shift;

  $self->prefixspan("", $self->{data});

  return $self->{out};
}


sub prefixspan {
  my $self = shift;
  my $prefix = shift;
  my $seq = shift;

  if (ref $seq eq "ARRAY") {
    my $pattern = $self->extract($self->{minsup}, $seq);
    if (ref $pattern eq "HASH") {

      foreach my $i (keys %{$pattern}) {
        my $p = $i;
        if ($prefix ne "") {
          $p = join " ", ($prefix, $i);
        }
        my $count = (() = $p =~ /\s+/g);
        if ($count >= $self->{len} - 1) {
          $self->{out}{"$p"} = $pattern->{$i};
        }
        my $j = $self->projection($seq, $i);
        $self->prefixspan($p, $j);
      }
    }
  }
}

sub extract {
  my $self = shift;
  my $minsup = shift;
  my $seq = shift;
  my $h;

  for (my $i = 0; $i < @$seq; $i++) {
    my @dist = split /\s+/, $seq->[$i];
    map {$h->{$_}++} @dist;
  }
  foreach my $i (keys %{$h}) {
    if ($h->{$i} < $minsup) {
      delete $h->{$i};
    }
  }

  return $h;
}

sub projection {
  my $self = shift;
  my $seq = shift;
  my $b = shift;
  my $h;

  foreach my $i (@{$seq}) {
    my @list = split /\s+/, $i;
    for (my $j = 0; $j < @list; $j++) {
      if ($list[$j] eq $b) {
        splice @list, 0, ($j +1);
        if (@list > 0) {
          push @{$h}, join " ", @list;
        }
      }
    }
  }

  return $h;
}


1;
__END__